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71.
Synthesis of several prostaglandin-F1 related compounds utilizing bicyclo(2,2,1) heptene derivatives as key intermediates were investigated.  相似文献   
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The present study was conducted to know the effects of different light intensities exposed during daytime for several hours on melatonin excreting rate in urine and tympanic temperature. Eleven healthy female subjects were exposed to bright light of 6000 lx (Bright) or dim light of 100 lx (Dim) during daytime from 09:00 h to 13:30 h, and then the light condition was kept at 100 lx until the end of test at 14:30 h. The urinary samples were collected from 10:00 h to 14:30 h every 1.5 hours, and melatonin excreting rate in urine was measured by enzyme immunoassay. Melatonin excreting rate in urine was significantly higher in Bright than in Dim at 11:30 h and 14:30 h, and not significant but at high level at 13:00 h (p <0.07). Moreover, average tympanic temperatures were significantly lower in Bright than in Dim from 11:43 h to 14:30 h. These results showed that the bright light exposure during daytime could reduce tympanic temperature, which might result from the increase of melatonin level.  相似文献   
74.
The present experiment investigated the effects of skin pressure by foundation garments (brassiere plus girdle) worn during wakefulness on the circadian rhythms of core temperature and endocrine secretion. Eight healthy females (18–23 yrs) maintaining regular sleep-wake cycles for a week prior to participation in the experiment served as participants. The experiments were performed from June to August, 1999, using a bioclimatic chamber controlled at 26.5 ± 0.2°C and 62 ± 3% RH. Ambient light intensity was controlled at 500 lx from 07:30 h to 17:30 h, 100 lx from 17:30 h to 19:30 h, 20 lx from 19:30 h to 23:30 h and there was total darkness from 23:30 h to 07:30 h. The experiment lasted for 58?h over 3 nights. The participant rose at 07:30?h in the morning of the first day and retired at 23:30 h, adhering to a set schedule for 24 h but without wearing foundation garments. From 07:30 h to 23:30 h of the second day the participant wore foundation garments but did not wear foundation garments during the sleep. Rectal and leg skin temperatures were continuously measured throughout the experiment. Urine was collected every 4 h for the analysis of catecholamines. Skin pressure applied by the foundation garments was in the range 11–17 gf/cm2 at the regions of abdomen, hip, chest and back. The main results were as follows: Rectal temperature was significantly higher (p < 0.01) during wakefulness, but significantly lower (p < 0.01) during sleep with than without foundation garments. Furthermore, the amplitude of rectal temperature was larger with than without foundation garments (p < 0.033). Urinary noradrenaline was mostly lower with foundation garments throughout the day and night. The results suggest that skin pressure by foundation garments worn during wakefulness could influence the level of core body temperature and noradrenaline secretion not only during wakefulness, but also during sleep.  相似文献   
75.
After fertilization, the sperm and oocyte genomes undergo extensive epigenetic reprogramming to form a totipotent zygote. The dynamic epigenetic changes during early embryo development primarily involve DNA methylation and demethylation. We have previously identified Gse (gonad-specific expression gene) to be expressed specifically in germ cells and early embryos. Its encoded protein GSE is predominantly localized in the nuclei of cells from the zygote to blastocyst stages, suggesting possible roles in the epigenetic changes occurring during early embryo development. Here, we report the involvement of GSE in epigenetic reprogramming of the paternal genome during mouse zygote development. Preferential binding of GSE to the paternal chromatin was observed from pronuclear stage 2 (PN2) onward. A knockdown of GSE by antisense RNA in oocytes produced no apparent effect on the first and second cell cycles in preimplantation embryos, but caused a significant reduction in the loss of 5-methylcytosine (5mC) and the accumulation of 5-hydroxymethylcytosine (5hmC) in the paternal pronucleus. Furthermore, DNA methylation levels in CpG sites of LINE1 transposable elements, Lemd1, Nanog and the upstream regulatory region of the Oct4 (also known as Pou5f1) gene were clearly increased in GSE-knockdown zygotes at mid-pronuclear stages (PN3-4), but the imprinted H19-differential methylated region was not affected. Importantly, DNA immunoprecipitation of 5mC and 5hmC also indicates that knockdown of GSE in zygotes resulted in a significant reduction of the conversion of 5mC to 5hmC on LINE1. Therefore, our results suggest an important role of maternal GSE for mediating active DNA demethylation in the zygote.  相似文献   
76.
Successful invasion by nonindigenous species is often attributed to high propagule pressure, yet some foreign species become widespread despite showing reduced genetic variation due to founder effects. The signal crayfish (Pacifastacus leniusculus) is one such example, where rapid spread across Japan in recent decades is believed to be the result of only three founding populations. To infer the history and explore the success of this remarkable crayfish invasion, we combined detailed phylogeographical and morphological analyses conducted in both the introduced and native ranges. We sequenced 16S mitochondrial DNA of signal crayfish from across the introduced range in Japan (537 samples, 20 sites) and the native range in western North America (700 samples, 50 sites). Because chela size is often related to aggressive behavior in crayfish, and hence, their invasion success, we also measured chela size of a subset of specimens in both introduced and native ranges. Genetic diversity of introduced signal crayfish populations was as high as that of the dominant phylogeographic group in the native range, suggesting high propagule pressure during invasion. More recently established crayfish populations in Japan that originated through secondary spread from one of the founding populations exhibit reduced genetic diversity relative to older populations, probably as a result of founder effects. However, these newer populations also show larger chela size, consistent with expectations of rapid adaptations or phenotypic responses during the invasion process. Introduced signal crayfish populations in Japan originate from multiple source populations from a wide geographic range in the native range of western North America. A combination of high genetic diversity, especially for older populations in the invasive range, and rapid adaptation to colonization, manifested as larger chela in recent invasions, likely contribute to invasion success of signal crayfish in Japan.  相似文献   
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Chronic inflammatory diseases, such as rheumatoid arthritis and periodontitis-caused bone destruction, results from an increase of bone-resorbing osteoclasts (OCs) induced by inflammation. However, the detailed mechanisms underlying this disorder remain unclear. We herein investigated that the effect of urokinase-type plasminogen activator (uPA) on inflammatory osteoclastogenesis induced by lipopolysaccharide (LPS), which is a potent stimulator of bone resorption in inflammatory diseases. We found that the uPA deficiency promoted inflammatory osteoclastogenesis and bone loss induced by LPS. We also showed that LPS induced the expression of uPA, and the uPA treatment attenuated the LPS-induced inflammatory osteoclastogenesis of RAW264.7 mouse monocyte/macrophage lineage cells. Additionally, we showed that the uPA-attenuated inflammatory osteoclastgenesis is associated with the activation of plasmin/protease-activated receptor (PAR)-1 axis by uPA. Moreover, we examined the mechanism underlying the effect of uPA on inflammatory osteoclastogenesis, and found that uPA/plasmin/PAR-1 activated the adenosine monophosphate-activated protein kinase (AMPK) pathway through Ca2+/calmodulin dependent protein kinase kinase (CaMKK) activation, and attenuated inflammatory osteoclastogenesis by inactivation of NF-κB in RAW264.7 cells. These data suggest that uPA attenuated inflammatory osteoclastogenesis through the plasmin/PAR-1/Ca2+/CaMKK/AMPK axis. Our findings may provide a novel therapeutic approach to bone loss caused by inflammatory diseases.  相似文献   
80.
Chiral nanostructures show macroscopic optical activity. Local optical activity and its handedness are not uniform in the nanostructure, and are spatially distributed depending on the shape of the nanostructure. In this study we fabricated curved chain nanostructures made of gold by connecting linearly two or more arc structures in a two‐dimensional plane. Spatial features of local optical activity in the chain structures were evaluated with near‐field circular dichroism (CD) imaging, and analyzed with the aid of classical electromagnetic simulation. The electromagnetic simulation predicted that local optical activity appears at inflection points where arc structures are connected. The handedness of the local optical activity was dependent on the handedness of the local chirality at the inflection point. Chiral chain structures have odd inflection points and the local optical activity distributed symmetrically with respect to structural centers. In contrast, achiral chain structures have even inflection points and showed antisymmetric distribution. In the near‐field CD images of fabricated chain nanostructures, the symmetric and antisymmetric distributions of local CD were observed for chiral and achiral chain structures, respectively, consistent with the simulated results. The handedness of the local optical activity was found to be determined by the handedness of the inflection point, for the fabricated chain structures having two or more inflection points. The local optical activity was thus governed primarily by the local chirality of the inflection points for the gold chain structures. The total effect of all the inflection points in the chain structure is considered to be a predominant factor that determines the macroscopic optical activity. Chirality 28:540–544, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   
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